Answers

Subtract 21/84 from 90/70

1^st number: 1 20/70, 2^nd number: 21/84

90/70 - 21/84 is 29/28.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 84 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 70 × 6 = 420,
   90/70 = 90 × 6/70 × 6 = 540/420
3. Likewise, for the 2nd fraction, since 84 × 5 = 420,
   21/84 = 21 × 5/84 × 5 = 105/420
4. Subtract the two like fractions:
   540/420 - 105/420 = 540 - 105/420 = 435/420
5. After reducing the fraction, the answer is 29/28
6. In mixed form: 11/28

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